Management of the Parastomal Hernia A Park MD FRCS FACS University Of Maryland Baltimore, MD

Overview: Some Background – definitions, demographics Pathophysiology & mechanisms of formation Clinical presentation Management & Techniques of repair How well are we doing? Role of prophylaxis?

Defining Terms – Let’s Be Clear: A parastomal hernia is an incisional hernia related to an abdominal wall stoma (Carne 2003) …or even more broadly… Any palpable defect or bulge adjacent to the stoma detected when the pt is supine with legs elevated or while…straining when the pt is erect (Israelsson 2008)

Devlin’s Classification of PH: Helpful conceptually but of limited use clinical studies 4 types, difficult to distinguish in clinically: i) subcutaneous ii) interstitial iii) perstomal iv) intrastomal

Parastomal Hernias: Incidence 5% to 50% depending on definition & means of detection Higher rates more accurate?! Colostomy > ileostomy? Evidence limited Lower with loops since shorter duration of stoma

Factors in Formation of Parastomal Hernias: General pt factors (as with VH): obesity, malnutrition, COPD,  age, wound infection Trephine size (?!): - 1 vs 2 fingers (Babcock) - 1.5 cm (colon) vs 2 cm (ileum) - ⅔ width of “crushed” intestine (Nguyen)

Stoma Location & PH Formation: Never through laparotomy incision! (infection, dehiscence, hernia) Historically through umbilicus when paramedian incision used Through rectus muscle vs lateral R.A - limited evidence , no RCT data (2 of 6 retrospective studies suggest some benefit) Pre op siting - no hernia advantage although more convenient & comfortable!

PH:Clinical Presentation Most asymptomatic Mild to life threatening (strangulation) Often parastomal discomfort, int SBO Difficulty with stoma appliance – skin irritation, soilage Psychological issues- more difficult to conceal stoma , smell etc

Surgical Management of PH: Local Suture Repair (50-100% recurrence) Relocation of Stoma (36% recur BJS’03) Mesh Repair - Inlay vs Onlay vs IPOM (Sub/Underlay) - Open vs Lap

Stoma Relocation Should be to contralateral side - different quad same side… poor outcomes Suture repair (only) of original site- 26% recurrence Risk of recurrence at new site same as original(24-86%)even more if 2nd relocation

PH: Mesh Repair/Positioning Inlay-no role ,recurrence too high Onlay- on Anterior aponeurosis - concern re:infection ++ - Intra abd pressure can displace mesh - min. data (recur?10%) rarely done Sublay or IPOM , preferred by most - slit mesh vs “Sugarbaker”

PH: Open Mesh repair Results (Carne ’03, Israelsson ’08) No prospective studies (let alone RCTs) Data paltry, low recur. Short f/u (?) Infection rates low …although… Mesh related complications can be high Presented opportunity for Lap approach

Rubin et al , Arch Surg 1994 68 parastomal repairs (55 patients) f/u median 31 months Local (fascial) repair- 36 (53%) Stoma Relocation - 25 (37%) Mesh Repair (mostly onlay) - 7 (10%)

Rubin (cont.) 63% overall recurrence Local repair -76% Stoma Relocation- 33% (52% got incisional hernia) Mesh repair - 30%

Berger et al (Dis Colon Rectum ‘07) Retrospective study 1999-2006 66pts ( 22 recur hernias)- no conversions “Sugarbaker” & slit double mesh technique Median 24 mo f/u - 12% recurrence 3 major infections with mesh removal

Mancini et al (Surg Endosc ’07) Multi-institute consecutive series 2001-2005 25 pts (6 recurrent hernias)- no conversions Largely “Modified Sugarbaker” Median f/u 19 mos. 4% recurrence 23% morbidity ( infectious,ileus,pulmonary)

Prevention of Parastomals (Janes, Israelsson et al BJS 2004) Prospective Randomize Trial: Pts undergoing colostomy w/wo sublay mesh ( light weight ,partially absorbable) 2001-2003 54 pts entered(27/27) - periop morbidity same At 12mos f/u: 18 no mesh – 8 recurrences 16 with mesh – 0 recurrences Study discontinued although f/u continues

Conclusions Parastomal hernia remain a common sequela of stoma formation (Mercifully) many are asymptomatic requiring no treatment Surgical repair remains a challenge with suboptimal outctomes Mesh repair (underlay) shows most promise Must strongly consider prophylactic mesh